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Cooper Bussmann BU-245U-E Wireless Ethernet & Device Server User Manual
APPENDIX B GLOSSARY
3A1576Rev1.6
ACK
Acknowledgment.
Access Point
An access point connects wireless network stations (or clients) to
other stations within the wireless network and also can serve as the
point of interconnection between the wireless network and a wired
network. Each access point can serve multiple users within a defined
network area.Also known as a base station.
Antenna Gain
Antennae don’t increase the transmission power,but focus the signal
more. So instead of transmitting in every direction (including the sky
and ground) antenna focus the signal usually either more horizontally
or in one particular direction.This gain is measured in decibels
Bandwidth
The maximum data transfer speed available to a user through a
“network.”
Bridge
A bridge is used to connect two local area networks together.Bridges
are typically used to connect wireless networks to wired networks.
Typically,bridges will transfer messages between networks only when
the message destination is on the other network. Messages that are
destined for the same network as they originated on are not passed to
the other network, therefore reducing traffic on the entire network.
Collision Avoidance
A network node procedure for proactively detecting that it can transmit
a signal without risking a collision with transmissions from other
network nodes.
Client / Sta / Station
A device on a network that gains access to data, information,and
other devices through a Server (Access Point).
Crossover Cable
A special cable used for networking two computers without the use of
a hub. Crossover cables may also be required for connecting a cable
or DSL modem to a wireless gateway or access point.The cable is
wired so that the signals “crossover”,connecting transmit signal on
one side to receiver signals on the other.
CSMA/CA
Carrier Sense Multiple Access/Collision Avoidance is a "listen before
talk" method of minimizing (but not eliminating) collisions caused by
simultaneous transmission by multiple radios. IEEE 802.11 states
collision avoidance method rather than collision detection must be
used, because the standard employs half duplex radios—radios
capable of transmission or reception—but not both simultaneously.
Unlike conventional wired Ethernet nodes, a WLAN station cannot
detect a collision while transmitting. If a collision occurs,the
transmitting station will not receive an ACKnowledge packet from the
intended receive station. For this reason,ACK packets have a higher
priority than all other network traffic.After completion of a data
transmission, the receive station will begin transmission of the ACK
packet before any other node can begin transmitting a new data
packet.All other stations must wait a longer pseudo randomized
period of time before transmitting. If an ACK packet is not received,
the transmitting station will wait for a subsequent opportunity to
retry transmission.
CSMA/CD
Carrier Sense Multiple Access/Collision Detection is the access
method used on an Ethernet network.A network device transmits data
after detecting that a channel is available. However,if two devices
transmit data simultaneously,the sending devices detect a collision
and retransmit after a random time delay.
DHCP
Dynamic Host Configuration Protocol A utility that enables a server to
dynamically assign IP addresses from a predefined list and limit their
time of use so that they can be reassigned.Without DHCP, an IT
Manager would have to manually enter in all the IP addresses of all
the computers on the network.When DHCP is used, whenever a
computer logs onto the network, it automatically gets an IP address
assigned to it.
Dial-Up
A communication connection via the standard telephone network, or
Plain Old Telephone Service (POTS).
DNS
Domain Name Service A program that translates URLs to IP addresses
by accessing a database maintained on a collection of Internet
servers. The program works behind the scenes to facilitate surfing the
Web with alpha versus numeric addresses.A DNS server converts a
name like mywebsite.com to a series of numbers like 107.22.55.26.
Every website has its own specific IP address on the Internet.
DSL
Digital Subscriber Line Various technology protocols for high-speed
data, voice and video transmission over ordinary twisted-pair copper
POTS (Plain Old Telephone Service) telephone wires.